Adhesive of a silicon and silica composite for bonding together silicon parts

• US 7,666,513 B2
• Filed: 06/01/2006
• Issued: 02/23/2010
• Est. Priority Date: 04/23/2003
• Status: Active Grant

• Current Assignee: Hangzhou Dunyuanjuxin Semiconductor Technology Company Limited
• Original Assignee: Integrated Materials, Inc. (Ferrotec Holdings Corporation)
• Inventors: Boyle, James E., Zehavi, Raanan, Chalzel, Amnon
• Primary Examiner(s): Speer; Timothy M
• Assistant Examiner(s): Langman; Jonathan C
• Application Number:
  US11/444,560
• Publication Number:
  US 20060213601A1
• Time in Patent Office: 1,363 Days
• Field of Search: 156/48, 156/329, 156/89.11, 501/4, 501/53, 501/95.2, 501/154, 428/208, 4283171-3179, 428/318.4, 428/318.6, 428/312.6, 428/426, 428/428, 428/446, 428/448, 427/219, 206/454, 211/41.18, 432/253, 432/258
• US Class Current: 428/446
• CPC Class Codes: H01L 21/67306 characterized by a material, a roughness, a coating or the like
• CPC Class Codes: Y10T 428/24174 including sheet or component perpendicular to plane of web or sheet
• CPC Class Codes: Y10T 428/25 Web or sheet containing structurally defined element or component and including a second component containing structurally defined particles
• CPC Class Codes: Y10T 428/252 Glass or ceramic [i.e., fired or glazed clay, cement, etc.] [porcelain, quartz, etc.]
• CPC Class Codes: Y10T 428/26 Web or sheet containing structurally defined element or component, the element or component having a specified physical dimension

Abstract

A method of joining two silicon members, the adhesive used for the method, and the joined product, especially a silicon tower for supporting multiple silicon wafers. A flowable adhesive is prepared comprising silicon particles of size less than 100 μm and preferably less than 100 nm and a silica bridging agent, such as a spin-on glass. Nano-silicon crystallites of about 20 nm size may be formed by CVD. Larger particles may be milled from virgin polysilicon. If necessary, a retardant such as a heavy, preferably water-insoluble alcohol such as terpineol is added to slow setting of the adhesive at room temperature. The mixture is applied to the joining areas. The silicon parts are assembled and annealed at a temperature sufficient to link the silica, preferably at 900° C. to 1100° C. for nano-silicon but higher for milled silicon.

Claims

1. A substrate support fixture, comprising:

a plurality of silicon legs including teeth for supporting a plurality of substrates in parallel orientations;

two silicon bases joined to opposing ends of the legs across respective joints with respective gaps between a respective one of the bases and a respective one of the legs;

silicon crystallites having sizes of less than 100 μ

m occupying at least 50% of the gaps; and

a silica network in each of the gaps joining and adhering the silicon crystallites and the legs and the bases.

2. The fixture of claim 1, wherein the sizes are between 1 and 75 μ

m.

3. The fixture of claim 1, wherein the silicon crystallites have a size distribution with at least 99% of particles having a size of less than 100 nm.

4. The fixture of claim 1, wherein the legs comprise an arcuate back side opposite the tips of the teeth supporting the substrates.

5. The fixture of claim 1, wherein the silicon crystallites have at least interiors consisting essentially of silicon.

6. A silicon assembly comprising at least two silicon parts bonded together along respective joining areas by the method of:

providing a mixture of a powder consisting essentially of silicon and a chemical which when annealed to an annealing temperature vitrifies to form a silicate glass;

applying the mixture to at least one of the joining areas;

assembling the at least two silicon parts with the respective joining areas in juxtaposition; and

annealing the assembled parts at the annealing temperature to thereby bond the parts together, wherein the at least two silicon parts include two silicon bases and at least three silicon legs bonded on ends thereof to the silicon bases and including teeth formed therein for supporting a plurality of substrates in a stacked arrangement.

7. The assembly of claim 6, wherein the silicon parts consist essentially of silicon.

8. A substrate support fixture, comprising:

a plurality of silicon legs including teeth for supporting a plurality of substrates in parallel orientations;

two silicon bases joined to opposing ends of the legs across respective joints with respective gaps between a respective one of the bases and a respective one of the legs; and

a composite bridging each of the gaps, adhering the parts together, and comprising silicon crystallites having a least interiors consisting essentially of silicon, embedded in a matrix of silica, and occupying at least 50% of each of the gaps.

9. The fixture of claim 8, wherein the silicon crystallites have sizes of less than 100 microns.

10. The fixture of claim 8, wherein the silica comprises no more than 11% of the composite.

11. A substrate support fixture, comprising:

a plurality of silicon legs including teeth for supporting a plurality of substrates in parallel orientations;

two silicon bases joined to opposing ends of the legs across respective joints with respective gaps between a respective one of the bases and a respective one of the legs;

a silica network bridging the respective gap; and

silicon particles having at least interiors consisting essentially of silicon embedded in the matrix and occupying at least 50% of the respective gap.

12. The fixture of claim 11, wherein the silicon particles have sizes of less than 100 microns.